不同气体吸入对高原缺氧犬脑脊液及动脉血酸碱值的影响

Effects of Breathing Different Air Containing 3% Carbon Dioxide, 95% Oxygen or a Mixture of 3% Carbon Dioxide/95% Oxygen on Acid-base Variables of Cerebrospinal(CSF) and Arterial Blood in High-altitude Hypoxic Dogs

目的:了解氧气(O2)、二氧化碳气(CO2)及氧气与二氧化碳混合气(O2/CO2)对急性高原病的防治情况。方法:15条杂种犬放入减压舱,以3m/s的速度到达4500m高度,持续减压3天,造成急性高原缺氧模型,然后利用右心漂浮导管法对急性缺氧犬分别吸入O2、CO2及O2+CO2,动态观察动脉血及脑脊液酸碱值的变化情况。结果:急性缺氧犬分别吸入O2、CO2及O2+CO2后,各组自身前后比较,氧气组能提高SaO2、PaO2、PaCO2(P<0.001～P<0.05),但对血液和CSF中pH、HCO3-的改善不明显;CO2组能提高血液和CSF中pH、HCO3-、PaCO2(P<0.001～P<0.05),但不能提高SaO2、PaO2;CO2/O2组则既有益于提高血液和CSF中PaO2、PaCO2、HCO3-,又能降低pH(P<0.001～P<0.05)。结论:CO2/O2混合对高原缺氧有一定的协同作用,优于CO2及O2的单独使用,可能对AMS的防治有益。

Objective： To observe the preventive and therapeutic effects of carbon dioxide, oxygen or a mixture of carbon dioxide/oxygen on acute mountain sickness. Methods： The acid--base variables of arterial blood and eerebrospinal fluid（CSF）in acute hypoxie dogs were observed dynamically through Swan-Ganz catheter. Results： After breathing 95% O2 in acute hypoxia dogs, oxygen saturation（SaO2） .partial pressure of O2 （PaO2） and partial pressure of CO2 （PaCO2）in arterial blood and eerebrospinal fluid were increased, there are significant difference compared with those before breathing 95% O2 （P〈0. 001-P〈0.05, but no change in pH, HCO3^-. After breathing 3 % CO2 in acute hypoxia dogs compared with those before breathing 3 % CO2, HCO3^- ,partial pressure of CO2 （PaCO2） in arterial blood and eerebrospinal fluid were improved（P〈0. 001 - P〈0.05）, but SaO2, PaO2 have not marked changes. After breathing a mixture of carbon dioxide/oxygen in acute hypoxia dogs compared with those before breathing a mixture of carbon dioxide/oxygen, level of SaO2 .PaO2 .HCO3^-,PaCO2 and pH were improved（P〈0. 001-P〈0.05）. Conclusions. Our results show that the combination of CO2 with O2 has a synergistic effect and is better than CO2 or 02 alone and could be useful in the prevention of AMS.